A practical approach to the implementation of selectivity in homonuclear multidimensional NMR with frequency selective-filtering techniques. Application to the chemical structure elucidation of complex oligosaccharides
C. Roumestand et al., A practical approach to the implementation of selectivity in homonuclear multidimensional NMR with frequency selective-filtering techniques. Application to the chemical structure elucidation of complex oligosaccharides, MAGN RES CH, 37(7), 1999, pp. 451-478
This review describes the use of frequency-selective filters for the design
of selective NMR experiments. Frequency-selective filters constitute 'user
-friendly' and efficient alternatives to selective excitation in most appli
cations. Different selective schemes are discussed, which are based either
on selective inversion or selective refocusing of the frequencies of intere
st. Selective filters can be used to transform 2D (or 3D) experiments into
1D (or 2D) analogues, or to restrict the matrix size in higher dimensional
spectra. Accurate NMR parameters can be easily extracted from such spectra
in short measuring times, with high digital resolution and minimum data sto
rage. For these reasons, these experiments are a very useful alternative to
conventional multidimensional experiments in structural and/or conformatio
nal studies of small- and medium-sized molecules. Moreover, using DANTE pro
cedures for selectivity, they can be easily implemented on 'routine' spectr
ometers, without the need for sophisticated hardware. These methods have be
en tested on a complex heterosidic compound, where they prove to afford out
standing interest in achieving proton resonance assignment and chemical str
ucture delineation. Copyright (C) 1999 John Wiley & Sons, Ltd.